What Makes a Family: The Red Thread
by ficdirectory
Summary: AU. Set in the What Makes a Family Universe. Christmas is just around the corner, and Aaron and Penelope have more in common than he realized. Written for the 2012 Christmas Gift Fic Exchange. Big thanks to musewars for the beautiful cover!


**A/N: Written for amyprentiss-reid, as a part of the 2012 Christmas Gift Fic Exchange on the CCOAC forum. She requested the characters Hotch and Garcia, and prompts: O Holy Night, snowflakes, midnight and tinsel. Merry Christmas (a little early), amyprentiss-reid! Hope you enjoy this!**

Aaron wasn't so sure about this. Not when Mom said she was taking everybody out shopping the day after Thanksgiving. He didn't like crowds. He could never trust that he wasn't going to see his biological mom and dad. He never _had _seen them randomly, but he never wanted to, either. In fact, he made such a big deal out of not wanting to go that Mom decided she would take Derek, JJ and Spencer, and leave Aaron at home with Penelope. It was kind of exactly what he wanted.

Penelope was twenty. She didn't really live with them, but it was like she did. She was always there for the important days, like Thanksgiving and all their birthdays. His birthday was in eleven days. Aaron would be ten. Even though he'd been living with his mom in this house for almost three years, he still wondered if he would get presents. His birthday was only a couple weeks before Christmas, so it wasn't like he needed things twice in one month.

Everything was so confusing. Aaron was having a hard time. Probably because he moved here in December, and December was on its way. That month didn't have good memories, so he was in a bad mood a lot.

But the minute all the rest of the family left, Penelope came knocking at Aaron's bedroom door. He could hear Christmas songs that sounded old-fashioned coming from downstairs. "Hey, Mr. President. Why so glum?" she asked, coming and sitting on his bed.

"I hate December," he mumbled.

"Oh. Well, lucky for you, it's still November! So, what do you say, we surprise the fam with some totally stellar Christmas decorations when they come home?"

"No," Aaron said, turning his back and staring at the wall.

"Come on. It'll be really fun. I promise," she said, pulling him up by the hand. "We'll decorate and surprise the socks off everyone when they come back from their big shopping extravaganza."

"You can be in charge of the fancy towels and snow globes. Oh! And the snowflake decals for the windows!" Penelope said hurriedly, heading for the stairs.

"What will _you _be in charge of?" he grumbled.

"Music…and tinsel!" she exclaimed. "Be right back. Just go in the kitchen cabinet and grab any Christmas-themed fancy looking towels, and replace the boring ones."

Aaron sighed, and got to work. Penelope made everything sound fun, but he knew work when he saw it. He also knew a mean trick when he saw one. When Penelope came back upstairs lugging a big green plastic container, Aaron stumbled back. He tripped on a chair and went sprawling, but didn't even feel the pain. He just moved as quick as he could into a corner.

"Hey, what's the deal?" Penelope asked gently, abandoning the big box and walking over to him.

Aaron flinched. "I'm sorry," he gasped.

"Hey…it's just me. You don't have to apologize. I'm just getting decorations, remember? I'm sorry if I was totally loud dragging that thing upstairs. I have absolutely no natural grace." She offered him a smile.

"So, that box…" Aaron ventured, his voice low and hoarse. "It's not supposed to be for me?"

"No…" Penelope ventured, clearly confused. "Why would you be terrified that I have a box for you?"

"Because what if I need consequences for a bad attitude?" he asked, looking at his socks.

Penelope's gaze softened, though she was still clearly confused. "Like _I'm _really the person to give _anybody _consequences for a bad attitude. I didn't tell you this, but I'm not a huge fan of December either."

"Is it because your parents used to treat you so bad but you still missed them when you came here?" Aaron guessed.

"No, it's because my parents died in December. I moved in with Emily in December, too, and had the worst attitude ever, remember?"

"Not really…" Aaron admitted. "I only remember you when you were good."

"Well, thanks," Penelope smiled ruefully. "Anyway, if this Christmas decorating is freaky for you, we don't have to do it. I just thought it'd be fun."

"No, we can…I just…don't really get it. Why do we have to do all this stuff? I thought it just magically happened…"

"Nope, sorry. Emily makes it magically happen."

"Oh," Aaron said, sounding contemplative. "So, if we did this, it would help Mom. Do you think she'd be happy?"

"Definitely. I know you're pretty new to this Christmas thing as a Prentiss, but as you get older, you'll see that the best part is definitely giving," Penelope slid an arm around him and Aaron relaxed against her. He felt safe. Like he could maybe help now, as long as Penelope did it with him.

"What Christmas is this for you?" he asked seriously.

"What _Christmas_?" she repeated.

"Yeah, like what number?" he asked.

"I guess, my twentieth. What Christmas will it be for you?" she wondered.

"My third…but I don't really remember the first two…" he told her seriously.

"No wonder you thought the house magically decorated itself," she teased gently.

Aaron laughed, getting to his feet. "Yeah, so I need you to teach me things. Because I don't want to ask Mom. I'll feel weird."

"You got it. What do you need to know?" Penelope asked, going through the pantry to locate all the Christmas towels, while Aaron righted the chair he tipped over.

"What's tinsel?" he asked. "And what's a mistletoe? And why do people kiss under it? How does Santa know who to bring presents to and who to skip? Can we bake Christmas cookies and what's the best Christmas song?"

"Holy cow. Okay. Sounds like we need some beverages for this. What do you say to some hot chocolate?" she asked.

"That's a trick question, right? You know I love hot chocolate," Aaron grinned.

"Right you are. Let's get some going. I'm adding candy canes for extra Christmas spirit," she told him.

They sat down at the table, with cups of hot chocolate in hand. Aaron stirred his with a candy cane, intrigued. He wondered how it would taste, but then remembered that if Penelope said it was good, then it must be.

"Okay, your questions…" Penelope said thoughtfully. "This is tinsel," she said, typing some buttons on her phone and showing him a picture. When Aaron saw it, he knew there was some in one of those boxes Penelope dragged upstairs, but he was glad she didn't go over there to show him.

"Oh! I know what that is! So, it's like garland?"

"Exactly!" Penelope exclaimed. "So, how's the hot chocolate? Up the president's standards?"

Aaron took a sip. "Mmmm…it's so good. Thank you."

"You're welcome. Now what else were you wondering?"

"What's mistletoe and why are Dave and Carolyn always kissing under it?" Aaron asked wrinkling his nose.

"It's a plant, and I think the kissing thing has been a tradition for years and years. It's just a nice gesture of friendship or goodwill."

"So, they just kiss because they're used to it and because they want to keep liking each other?" Aaron asked.

"I guess…" Penelope laughed. "Now, you were wondering about cookies, and I definitely have that on the agenda. Santa doesn't skip people. It's just that there are a lot of kids and only one of him, so sometimes he doesn't get to everybody. But we can help out by donating toys to kids who might not have any. Also," she said, thinking, "the best Christmas song is a matter of opinion. But to me, it's always been _O Holy Night._"

"Oh, how does it go?" Aaron asked. His family wasn't shy about singing. They sang all the time. True to form, Penelope sang a few lines, and Aaron immediately knew it was his favorite Christmas song, too. He wanted to hear more, so Penelope ended up singing the whole thing. Then, Aaron was determined to learn it, too.

It turned out to be a great day. When Mom got home, she was so surprised, she hugged and kissed both of them.

Weeks passed, and soon it was Christmas Eve. Aaron still didn't like December, but now at least, he knew all the words to _O Holy Night_. Penelope was sleeping over again. She was in JJ's room, and Aaron was hoping Spencer would sleep past 2 a.m. in his excitement to see what Santa brought them.

Aaron groaned when he felt a tap on his shoulder. He peeked at his clock and saw it was midnight. Spencer was getting up earlier than normal, and Aaron wasn't happy. He tried to ignore the tapping, until a voice that wasn't Spencer's whispered, "Wake up. It's Christmas."

Penelope. Penelope? Why was she in here?

Aaron rolled over and rubbed his eyes."What?" he asked groggily.

"I figured with this being your third official Christmas my twentieth, we should have something alike."

She dropped something on the bed, and he saw it sparkle in the dark. Penelope turned the bedside lamp on so he could see. It was a red and silver bracelet. He stared at it, and then at her wrist, which had a matching one.

"How much did this cost?" Aaron asked breathlessly.

"That doesn't matter. It's a gift, so no paying me back. See how it's red here? There's an old Chinese legend that says '_An invisible red thread connects those who are destined to meet, regardless of time, place, or circumstance. The thread may stretch or tangle, but never break_.'

"So, you got one of these for everybody?" he wondered.

"Nope, just you," Penelope told him softly.

"How come?" he asked.

"Because we were destined to meet. Because I was clearly meant to be your quirky, crazy older sister, who teaches you about Christmas and anything else you could possibly want to know. Because you matter… Because we're the Decembers," she whispered.

_The End._


End file.
